Oxygen is more electro negative yet in the redox reaction

$$\ce{2PbO(s) -> 2Pb(s) + O2(g)}$$

my text book says lead is reduced and oxygen is oxidized. How can this be? It doesn't make sense to me. Oxygen is usually $2-$ while lead is usually $2+$.

• Oxidation is by definition a loss of electrone(s). $\ce{2O^{2-} - 4e -> O2^0}$ is an oxidation of oxygen. I honestly don't see what confuses you so much. – andselisk Jul 15 '17 at 6:01
• I agree with the OP that oxidation is a confusing word, especially if applied to the element oxygen. It would be better to say, in the example given, that the lead(+2) cation is reduced to elemental lead (0) and the oxide (-2) anion is oxidized to elemental oxygen (0). By analogy: converting chloride ion to chlorine gas is clearly oxidation, so the same is true for oxygen. – iad22agp Jul 15 '17 at 10:43

$$\ce{PbO (s, red)}, \Delta G^{\varnothing}_{f}=-189.3\ \mathrm{kJ}\ \mathrm{mol}^{-1}$$ or $$\ce{PbO (s, yellow)}, \Delta G^{\varnothing}_{f}=-188.5\ \mathrm{kJ}\ \mathrm{mol}^{-1}$$